Steel portal frame erected on new pad foundations, Great Holland, Essex — Mansouri Design & Build
Extensions & New Builds — New Builds

Sometimes the answer is a different house.

New homes on individual plots, replacement dwellings, and demolition and rebuild — designed and built by one team, in a modern idiom or matched to the local vernacular.

Where this starts

Extending is not always the right answer.

Most people come to us wanting more space, and for most of them an extension is the right way to get it. But there is a point past which extending stops making sense — where the foundations will not take it, where the roof structure fights every alteration, or where you would spend a very large sum and still be living in a house with the wrong plan and cold walls.

If your project is somewhere near that line, it is worth knowing which side of it you are on before you commission drawings for the wrong thing. We will tell you honestly — including when the answer is that extending is fine and rebuilding would be a waste of your money.

Ask us which applies

Signs a rebuild may beat a renovation

  • Foundations that will not carry the alterations you want
  • Structural movement that has already needed repair more than once
  • A roof structure that has to be substantially rebuilt anyway
  • Solid walls, poor thermal performance and no practical way to insulate without losing the rooms
  • A layout that cannot be made to work at any reasonable cost
  • Services — wiring, plumbing, heating — all due for replacement at once

None of these decides it on its own. Three or four together usually do.

What we build

Three ways this work reaches us.

A one-off home on a plot

For a homeowner who has bought, inherited or is buying a building plot.

The most rewarding version of this work and the least standardised. The design starts from the plot rather than from a house type: where the sun falls, what the site can carry, what the planners will accept, and how you actually want to live. We take it from appraisal and design through planning and Building Regulations to a finished, warranted house — one contract, one point of contact.

  • Plot appraisal before you commit, including what the ground and the planning position realistically allow
  • Architecture and structural engineering coordinated in-house
  • Full planning application and discharge of conditions
  • Groundworks, substructure, superstructure, roof, envelope and full fit-out
  • Services, drainage and external works as one package

Demolition and rebuild

For an owner whose existing house is beyond economic repair, or too compromised to extend.

There is a point at which extending and patching costs more than starting again and still leaves you with the wrong house. Failed foundations, a roof structure that will not take the alterations, a layout that cannot be rescued, poor thermal performance on every elevation. Replacing the dwelling gives you the plot, the orientation and the garden you already own, with a building designed around how you live now.

  • Honest appraisal of whether rebuilding genuinely beats renovating for your property
  • Demolition, site clearance and disposal
  • Asbestos survey and licensed removal where required
  • New foundations designed for the ground rather than inherited from the old house
  • Full rebuild to current Building Regulations throughout

Developer and plot schemes

For developers and landowners with a consented site or one in planning.

We work with developers as a build partner on individual plots and small schemes, including sites where the scheme has to satisfy a conservation officer. Where a consent is conditioned on matching the local vernacular, the material detailing is the part that decides whether it is discharged — and that is work our own bricklaying team does rather than something we subcontract and hope for.

  • Build-only against your design team's drawings, or design and build
  • Single plots and small multi-unit sites
  • Traditional-material schemes where the consent demands a specific idiom
  • Itemised tender pricing against your documents so it is genuinely comparable
  • Programme and stage payments agreed before we start
How it looks

Modern, or built to look as though it has always been there.

A new building is not obliged to announce itself as new. What gives one away is rarely its shape — it is the brick, the bond, the mortar joint, the eaves detail and the depth of the window reveals. Those are the things we already get right on period buildings, and the same team does them on a new one.

Modern

Clean detailing, large openings, good insulation and airtightness, and the building services designed in rather than added on. A new build is the one chance to get orientation, glazing and thermal performance right from the start rather than compensating for decisions somebody made in 1890.

  • Contemporary elevations and generous glazing
  • High insulation and airtightness detailing
  • Underfloor heating and heat pump-ready services
  • Roof lanterns, structural glazing and steel openings

Matched to the local vernacular

In an Essex village, a conservation area, or beside a listed building, a new house often has to look as though it has been there longer than it has. That is a materials and detailing problem more than a drawing problem — the bond, the joint, the eaves, the reveal depth and the roof gauge are what give a new building away, not its shape. This is the same team and the same masons who do our heritage repair work.

  • Handmade and reclaimed brick, laid in the appropriate bond
  • Lime mortar and traditional joint profiles
  • Knapped flint panels and flint-and-brick walling
  • Green oak framing, porches and structural members
  • Clay plain tile and natural slate roofing
  • Cast iron or cast aluminium rainwater goods rather than plastic
Knapped flint panel set between brick piers, Colne Engaine, Essex — Mansouri Design & Build
The masonry, in our own work

Knapped flint panels between brick piers on a garden wall at Colne Engaine. It is a boundary wall rather than a house — but the flintwork, the bond, the mortar and the setting-out are the same skills a vernacular-matched new build depends on, done by the same people.

See the project
Worth knowing

How a new build differs from an extension.

The VAT position is better

The construction of a new qualifying dwelling is zero-rated for VAT, and where a building is demolished to ground level and a genuinely new dwelling built in its place, that work can qualify too. An extension to an existing house is standard-rated at 20%.

On a large project the difference is substantial and it can change which option is actually cheaper. The conditions in HMRC Notice 708 are specific — particularly around how much of the existing structure is retained, where keeping a single facade under a planning condition is treated differently from keeping more. We are builders, not tax advisers: take advice on your own scheme.

Planning is a bigger hurdle

Permitted Development does not build you a house. A new dwelling or a replacement dwelling needs full planning permission, and a replacement is usually assessed on whether the new building is materially larger than what it replaces, how it sits in the street, and what is lost.

In a conservation area, or where the plot sits within the setting of a listed building, the design will be judged on how it reads from the public realm — which is exactly where a vernacular-matched scheme earns its keep.

Everything is designed, not inherited

No surprises behind the plaster, no foundations of unknown depth, no drainage that is not where the drawing says. The whole building is specified before it is built, which makes both the programme and the price far more predictable than any renovation — the single biggest practical advantage of building new.

Regulations apply in full

There is no historic-building allowance on a new house. Current standards for thermal performance, airtightness, ventilation, overheating and accessibility apply in full, and they are designed in from the start rather than negotiated afterwards. Done properly that is an advantage: the house is warm, quiet and cheap to run because it was drawn that way.

A structural warranty is usually needed

A new dwelling normally needs a structural warranty, which is separate from a contractor's insurance — most mortgage lenders require one before they will lend against a newly built house. It is worth raising at the first conversation rather than at the end. Tell us what your lender or your buyers will need and we will set out exactly how it is to be arranged on your scheme before you are committed to anything.

Not sure whether to extend or rebuild?

The extensions pages set out what is achievable without replacing the house, and the heritage page covers what changes when the building is listed or in a conservation area.

ExtensionsHeritage

Got a plot, or a house that has run out of road?

Tell us about the site and what you are hoping for. We respond within 24 hours — and we will tell you if extending would serve you better.

Tell Us About Your Project 01787 727158

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